Lamination with protective films is commonly used to protect print substrates. The laminated product not only looks nice, but also protects from the aging process and environment. Such products typically include a media or substrate such as paper (documents, posters and photographs), polyvinyl chloride (PVC) plastic cards (credit cards, driver's license, or other identification cards), cardboard (packaging or posters), foam-board (presentation, exhibition or display pieces), etc., laminated on one or both sides with a transparent plastic film. The film can be glossy or matte or with a particular texture depending upon the application. Examples of such products include menus, book covers, presentation folders, boxes, video cassette cases, record and CD jackets and displays for stores and exhibition.
As noted, items to be laminated can be laminated using one-sided or two-sided laminations. The laminating and mounting process can be accomplished using heat and pressure (thermal lamination process) or pressure alone (pressure sensitive process). Usually the adhesive employed dictates the process to be used.
For certain applications, it is desired to mount a first substrate onto a supportive rigid second substrate, such as foam board, GATORBOARD®, PVC board, SYNTRA®, matt board, illustration board or cardboard (e.g., 24 pt. board).
In the thermal lamination process, the film, generally polypropylene, polyester, vinyl or nylon, has a layer of heat activated adhesive on one side. The adhesive side is placed against the article or articles to be laminated. The articles to be laminated take two forms: precut and continuous. Usually, the items to be laminated are precut, separated and stacked and then fed automatically or manually into the laminating machine. In the alternative, the articles are continuous or in roll form and fed into the machine. Once laminated, the product is cut at its ends (the leading edge and the trailing edge) and slit along its sides (the side margins).
The film can also be in the form of a discreet sheet, integrated with the substrate to be laminated or separate from the substrate to be laminated, or in continuous, web form. Discreet sheets are commonly used with pouches, e.g., driver's licenses, school pictures, posters, etc. In “pouch-type” laminations, the film is integrated with the substrate to be laminated. Specifically, the film is hingedly adhered to an edge of the substrate, typically foam board. The integral film has a heat activated adhesive on the side of the film facing the substrate.
In continuous form, the film is supplied to the laminator from a supply roll and in web form. Usually, the web of film is fed to the laminating machine from a supply roll and the articles to be laminated are supplied to the machine individually. If the lamination is to be one-sided, the film is supplied from a single roll; if the lamination is to be two-sided, the film is supplied from two, separate rolls, one above the article to be laminated and one below the article to be laminated.
The coatings or adhesives used on these films incorporate vinyl acetate into the backbone of the polyethylene polymer. The resulting resin is an EVA (Polyethylene Vinyl Acetate copolymer) or form thereof. These adhesives are not tacky at room temperature, but become tacky when heat is applied to them, e.g., over 175° F.
As noted previously, for certain applications, such as presentations, advertisements, exhibits, educational training, etc., it is desirable to mount the substrate to be laminated onto a supportive backing, such as a rigid substrate or semi-rigid substrate (e.g., foam board, GATORBOARD®, PVC board, SYNTRA®, matt board, illustration board and cardboard (e.g., 24 pt. board)). To simplify and clarify discussion, the item to be laminated will be called at times the “print substrate,” even though it does not necessarily need to be printed. In addition, the surface facing outwardly towards the viewer will be called the “front surface,” and the surface facing the backer board will be called the “back surface.”
Oftentimes such products can be large, about 24″×36″ inches or larger. If a tabletop or free standing laminator is used, there needs to be an in-feed area and an out-feed area to align the items to be laminated before they go into the laminator and to catch the items as they exit the laminator. Without such areas, the items to be laminated and the final laminated product can be dropped and/or damaged. More significantly, if the laminated board is not supported while exiting the machine, the board will bend or curl as the weight of the board with the forces of gravity drive the board downwardly.
In addition, in many print or finishing shops that laminate materials, space is an issue. Space can be very limited. Accordingly, there is a need for laminating equipment that takes up less space and has a small footprint.
The present invention addresses this shortcoming as well as others associated with the laminating process and the laminators existing today.